Robert Caro’s epic biography of Lyndon Johnson—this is the fourth volume of a planned five—was originally conceived and has been largely executed as a study of power. But this volume has been overtaken by a more pressing theme. It is a study in hate. The book’s impressive architectonics come from the way everything is structured around two poles or pillars—Lyndon Johnson and Robert Kennedy, radiating reciprocal hostilities at every step of the story. Caro calls it “perhaps the greatest blood feud of American politics in the twentieth century.” With some reservations about the word “blood,” one has to concede that Caro makes good his claim for this dynamic in the tale he has to tell.

There are many dramatic events, throughout the volume, that illustrate Caro’s theme. I begin with one that could seem insignificant to those not knowing the background on both sides, because it shows that even the slightest brush between these two triggered rancorous inner explosions. Johnson, newly sworn in as president, had just come back to Washington on Air Force One from the terrible death of John Kennedy in Dallas. Robert Kennedy sped up the steps to the plane and rushed fiercely down the length of the cabin through everyone standing in his way (including the new president) to reach Jacqueline Kennedy. Understandable that he would first of all want to comfort the widow? Yes, but. This was the first of many ways Bobby (called that throughout) tried in the first days to ignore the man who had ignominiously, in his eyes, supplanted his brother by a murder in the man’s own Texas.

Caro understands that Bobby was determined not to see Johnson, even if he saw him—so he did not see him. But Johnson saw him not seeing, and hated him the more. That is how hate narrows one—narrows what one wants to see, or is able to see, in order to keep one’s hatred tended and hard.